EP3211788A1 - Moteur électrique à induction à double alimentation - Google Patents

Moteur électrique à induction à double alimentation Download PDF

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Publication number
EP3211788A1
EP3211788A1 EP16156807.6A EP16156807A EP3211788A1 EP 3211788 A1 EP3211788 A1 EP 3211788A1 EP 16156807 A EP16156807 A EP 16156807A EP 3211788 A1 EP3211788 A1 EP 3211788A1
Authority
EP
European Patent Office
Prior art keywords
rotor
stator
induction motor
control device
current
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP16156807.6A
Other languages
German (de)
English (en)
Inventor
Lachezar Lazarov Petkanchin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nrg Tech Ltd
Original Assignee
Nrg Tech Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nrg Tech Ltd filed Critical Nrg Tech Ltd
Priority to EP16156807.6A priority Critical patent/EP3211788A1/fr
Priority to KR1020187024716A priority patent/KR101992251B1/ko
Priority to EP17702088.0A priority patent/EP3420633B1/fr
Priority to BR112018015726A priority patent/BR112018015726A2/pt
Priority to ES17702088T priority patent/ES2770370T3/es
Priority to JP2018535177A priority patent/JP6571876B2/ja
Priority to PCT/EP2017/051904 priority patent/WO2017144238A1/fr
Priority to AU2017223891A priority patent/AU2017223891B2/en
Priority to CN201780013465.2A priority patent/CN108702120A/zh
Priority to US16/078,026 priority patent/US10790773B2/en
Publication of EP3211788A1 publication Critical patent/EP3211788A1/fr
Priority to ZA2018/04518A priority patent/ZA201804518B/en
Withdrawn legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P23/00—Arrangements or methods for the control of AC motors characterised by a control method other than vector control
    • H02P23/08—Controlling based on slip frequency, e.g. adding slip frequency and speed proportional frequency
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P23/00—Arrangements or methods for the control of AC motors characterised by a control method other than vector control
    • H02P23/20—Controlling the acceleration or deceleration
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P9/00—Arrangements for controlling electric generators for the purpose of obtaining a desired output
    • H02P9/007—Control circuits for doubly fed generators
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P2207/00—Indexing scheme relating to controlling arrangements characterised by the type of motor
    • H02P2207/01—Asynchronous machines
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P2207/00—Indexing scheme relating to controlling arrangements characterised by the type of motor
    • H02P2207/07—Doubly fed machines receiving two supplies both on the stator only wherein the power supply is fed to different sets of stator windings or to rotor and stator windings
    • H02P2207/076—Doubly fed machines receiving two supplies both on the stator only wherein the power supply is fed to different sets of stator windings or to rotor and stator windings wherein both supplies are made via converters: especially doubly-fed induction machines; e.g. for starting

Definitions

  • This invention relates to an electric motor, in particular to an induction motor, and to a method to operate an electric motor, in particular an induction motor.
  • an object of the current invention to provide an electric motor, in particular an induction motor, with better ability for rotor field vector control, both in terms of direction and strength than prior art induction motors.
  • an electric motor in particular an induction motor, comprises a stator, a rotor and a control device which is arranged at the rotor, wherein the stator is adapted to induce EMF (electromotive force) into the rotor during operation, and wherein the control device is adapted to vary the rotor magnetic flux field strength and direction, relative to the rotor itself and/or the slip of the motor based on or in relation or using the induced EMF.
  • EMF electrostatic force
  • control device is adapted to vary the phase and/or the magnitude/amplitude of the rotor current to adapt the rotor magnetic flux field and power factor.
  • this is realized by using the induced EMF.
  • the current can be shifted forwards or backwards for synchronization with the induced EMF in the rotor.
  • the level, magnitude or amplitude of the current can be increased or decreased which means that the current in the windings can be varied/modulated.
  • control device is preferably adapted to vary the frequency and/or the magnitude/amplitude of the rotor current to adapt the slip.
  • the slip is defined as the difference between synchronous speed and operating speed at the same frequency, expressed in RPM or in percent of ratio of synchronous speed. Slip, which varies from zero at synchronous speed and one when the rotor is at rest, determines the motor's torque.
  • the rotor comprises a rotor winding or a plurality of rotor winding, respectively, electrically connected to the control device.
  • three rotor windings are mounted at 120° to each other and are connected in star or delta connection. This way, three-phase AC will be induced into the three windings due to rotating magnetic field around them. Frequency of the AC in the rotor will be equal to the slip frequency.
  • the control device is adapted to correct the power factor in all three rotor AC phases.
  • the control device is adapted to phase shift electrical current in all three rotor windings so that the current in any winding is in phase with the induced EMF in the rotor.
  • the prior art rotor constitutes a number of RL (inductive resistive) electric loops, causing a delay of current in every loop of the rotor with respect to the induced EMF in the loop.
  • the power factor of the rotor loops in prior art is less than 1, which offsets the rotor flux vector not to be at 90° with respect to stator mmf vector.
  • the control device is preferably an active control device comprising at least one control loop, for example a PI (Proportional Integral) control loop, and/or at least one PWM unit.
  • every PI control loop comprises a feed back or a loop controller.
  • the controller is adapted to operate the PI control loops and/or the PWM unit(s). The whole system is expediently arranged at the rotor and therefore spins or rotates with the rotor.
  • control device having a PWM unit, which comprises for example a plurality of transistors and diodes.
  • the windings of the rotor are electrically connected to the switching unit.
  • control device comprises a power supply unit adapted to power the control device with DC power.
  • the windings of the rotor are also electrically connected to the power supply unit.
  • the power supply unit comprises an energy storage unit adapted to store energy from the rotor.
  • the energy storage unit comprises at least one capacitor. These components are preferably also connected to the windings of the rotor. This allows to vary the phase and/or the magnitude/amplitude and/or the frequency of the rotor in order to adapt the power factor and/or the slip of the rotor.
  • the energy storage unit is a capacity bank in which electric energy is stored in the form of electric charge. This energy is then used to appropriately modulate frequency and/or magnitude/amplitude of rotor current vector so that it is kept as close as possible to 90° with respect to the stator mmf vector.
  • PWM module outputs sinusoidal PWM duty cycle which brings rotor current to come earlier and by doing so eliminates phase lag of rotor current in its otherwise purely RL circuits.
  • Frequency generated by the control device is kept equal to instantaneous slip frequency. When the control device increases its three-phase frequency, the slip also equally increases. More slip brings greater induced EMF in the rotor and the current in the rotor windings also increases which increases rotor flux.
  • the slip also decreases. Less slip brings drop in induced EMF in the rotor and the current in the rotor windings also drops which decreases rotor flux.
  • the rotor flux can be varied by adjusting the rotor PWM module duty cycle without having to adjust the slip. In this manner, the rotor flux can be advantageously varied depending on demanded torque.
  • the control device is powered entirely by the induced EMF in the rotor and does not need any additional power transfer modules like slip rings or electromagnetic exciters.
  • the electric motor can be operated as motor and/or as generator.
  • the rotor and/or the stator can also be provided with pole pair number switching devices to advantageously change the pole pair numbers of the electric machine during operation.
  • a rotor switching device is preferably attached to the rotor which means that it also rotates/spins with the rotor.
  • the rotor switching device does also not need any slip rings.
  • the induction motor comprises at least one position angle encoder, wherein the at least one position angle encoder is a rotor position angle encoder.
  • the rotor current vector is known exactly from measurements taken on the rotor itself and adding the angle of the shaft known from position angle encoder.
  • a sensorless method is used to determine the angle of the rotor flux vector.
  • the induction motor comprises at least one current sensor, wherein preferably at least two current sensors are positioned in the windings of the rotor.
  • the induction motor comprises an inverter module which is electrically connected to the stator, wherein the inverter module is preferably connected to the rotor control device via a communication unit.
  • the communication unit can be a wire- or wireless-based communication unit.
  • the inverter module is adapted to provide AC to the stator.
  • the inverter comprises also at least one control loop, for example a PI (Proportional Integral) control loop, and/or at least one PWM unit.
  • the inverter module is adapted to vary frequency, phase and/or the magnitude/amplitude of the current or voltage of the stator.
  • the invention refers also to a method to operate an electric motor, in particular an induction motor, having a stator and a rotor, comprising the step
  • a starting procedure of the electric motor may be as follows. Initially, there is no current in the rotor and the stator. Then, the inverter module generates a rotating magnetic field in the stator, modulating low voltage (low duty cycle) and generating a low frequency rotating current vector. EMF is induced in the rotor windings due to the stator rotating field. Diodes act as rectifiers and the capacitor(s) receive(s) electric charge.
  • the power supply device receives electric potential from the capacitor and powers up the rotor controller with appropriately regulated DC power. Rotor controller boots up and sends "ready signal" to inverter module via the communication unit. The rotor controller modulates the same low frequency rotating current vector with regard to the stator initial frequency. In such state, the rotor is not yet spinning as the slip frequency correlates to the stator frequency.
  • First step measuring of stator and rotor currents in two phases each using current sensors.
  • Second step estimating magnetic flux angles of rotor and stator ⁇ ( I rotor , I stator ) (knowing two measured rotor phase currents and two stator phase currents).
  • Rotor flux angle is determined by adding the angle of rotor physical position and rotor flux angle with respect to the rotor itself.
  • Rotor physical instantaneous position is determined from rotor position angle encoder.
  • Rotor flux angle with respect to the rotor itself is estimated on the basis of two measured currents in two rotor windings.
  • sensorless methods to estimate the angle ⁇ ( I rotor , I stator ) are known from the prior art. It is known that the angle between rotor and stator flux vectors affects stator current phase shift (back EMF).
  • the rotor flux vector on its turn also induces EMF in the stator.
  • This back EMF creates an additional current vector in the stator affecting the overall phase shift in the stator.
  • the rotor current vector I rotor is known exactly from measurements taken on the rotor itself, whereas in prior art it is estimated from the effects caused in the stator which is a lot slower and which is an inaccurate method.
  • Fig. 1 shows a schematic, perspective view of a motor with a rotor 40 comprising a shaft 90.
  • a control device 60 is attached to the rotor 40 or the shaft 90, respectively.
  • the rotor 40 comprises a rotor winding 42 comprising three windings 42 which are mounted at 120° to each other and which can be connected in star or in delta connection. This way, three-phase AC can be induced into the three windings 42 due to a rotating magnetic field of a stator (not shown).
  • the control device 60 is adapted to correct power factor and slip by varying the phase and/or magnitude/amplitude of rotor three phase current.
  • FIG. 2 shows a design scheme of an embodiment of an electric motor according to the invention.
  • a rotor 40 comprises a rotor winding 42 comprising/forming three phases.
  • the rotor 40 is combined with a control device 60.
  • the control device 60 comprises a controller 61 which is supported by a power supply unit 72 and an energy storage unit 74 comprising at least one capacitor 76.
  • the control device 60 comprises a PWM unit 66 comprising a plurality of transistors 68 and diodes 70.
  • the PWM unit 66 is electrically connected to the rotor winding 42 or the appropriate phases, respectively.
  • At least two phases of the rotor 40 are provided with a current sensor 80.
  • the rotor 40 comprises a rotor angle encoder 78.
  • the controller 61 or the control device 60, respectively, are connected to an inverter module 82 by a communication unit 84.
  • the inverter module 82 is electrically connected to a stator 20 which comprises also three phases wherein at least two phases comprise a current sensor 80.
  • the inverter module 82 is connected to a three phase AC system.
  • FIG. 3 shows a chart which visualizes different methods to operate an electric motor.
  • a control loop 62 preferably a PI control loop 62, and a PWM unit 64 are connected to a rotor 40. They process I stator , I rotor and ⁇ .
  • Two control loops 62 preferably two PI control loops 62, are connected to a stator 20. They process I stator , I rotor , ⁇ stator , ⁇ rotor , ⁇ shaft , ⁇ and commanded torque or commanded shaft RPM, respectively.
  • FIG. 3 different operation modes are described.
  • First step measuring of stator and rotor currents in two phases each using current sensors 80.
  • Second step estimating magnetic flux angles of rotor and stator ⁇ ( I rotor , I stator ) (knowing two measured rotor phase currents and two stator phase currents).
  • Rotor flux angle is determined by adding angle of rotor physical position and rotor flux angle.
  • Rotor physical instantaneous position is determined from rotor position angle encoder 78.
  • sensorless methods to estimate the angle ⁇ ( I rotor I stator ) are known from prior art. It is known that the angle between rotor and stator flux vectors affects stator current phase shift (back EMF). The rotor flux vector on its turn also induces EMF in the stator 20. This back EMF creates an additional current vector in the stator affecting the overall phase shift in the stator.
  • Fig. 4 shows a method to estimate magnetic flux angle from values of two known currents from three-phase current.
  • I 0 sin ⁇ t A t
  • I 0 sin ⁇ t + 2 3 ⁇ B t ,
  • a t is instantaneous current value in phase A and B t is instantaneous current value in phase B.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Control Of Ac Motors In General (AREA)
EP16156807.6A 2016-02-23 2016-02-23 Moteur électrique à induction à double alimentation Withdrawn EP3211788A1 (fr)

Priority Applications (11)

Application Number Priority Date Filing Date Title
EP16156807.6A EP3211788A1 (fr) 2016-02-23 2016-02-23 Moteur électrique à induction à double alimentation
JP2018535177A JP6571876B2 (ja) 2016-02-23 2017-01-30 二重給電誘導モータ
EP17702088.0A EP3420633B1 (fr) 2016-02-23 2017-01-30 Moteur électrique à induction à double alimentation
BR112018015726A BR112018015726A2 (pt) 2016-02-23 2017-01-30 Motor elétrico de alimentação dupla
ES17702088T ES2770370T3 (es) 2016-02-23 2017-01-30 Motor de inducción doblemente alimentado
KR1020187024716A KR101992251B1 (ko) 2016-02-23 2017-01-30 이중 여자 전기 모터
PCT/EP2017/051904 WO2017144238A1 (fr) 2016-02-23 2017-01-30 Moteur à induction à double alimentation
AU2017223891A AU2017223891B2 (en) 2016-02-23 2017-01-30 Doubly fed induction motor
CN201780013465.2A CN108702120A (zh) 2016-02-23 2017-01-30 双馈感应马达
US16/078,026 US10790773B2 (en) 2016-02-23 2017-01-30 Doubly fed induction motor
ZA2018/04518A ZA201804518B (en) 2016-02-23 2018-07-06 Doubly fed induction motor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP16156807.6A EP3211788A1 (fr) 2016-02-23 2016-02-23 Moteur électrique à induction à double alimentation

Publications (1)

Publication Number Publication Date
EP3211788A1 true EP3211788A1 (fr) 2017-08-30

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ID=55405252

Family Applications (2)

Application Number Title Priority Date Filing Date
EP16156807.6A Withdrawn EP3211788A1 (fr) 2016-02-23 2016-02-23 Moteur électrique à induction à double alimentation
EP17702088.0A Active EP3420633B1 (fr) 2016-02-23 2017-01-30 Moteur électrique à induction à double alimentation

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP17702088.0A Active EP3420633B1 (fr) 2016-02-23 2017-01-30 Moteur électrique à induction à double alimentation

Country Status (10)

Country Link
US (1) US10790773B2 (fr)
EP (2) EP3211788A1 (fr)
JP (1) JP6571876B2 (fr)
KR (1) KR101992251B1 (fr)
CN (1) CN108702120A (fr)
AU (1) AU2017223891B2 (fr)
BR (1) BR112018015726A2 (fr)
ES (1) ES2770370T3 (fr)
WO (1) WO2017144238A1 (fr)
ZA (1) ZA201804518B (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2694892C1 (ru) * 2018-10-15 2019-07-18 Федеральное государственное бюджетное учреждение науки Ордена Трудового Красного Знамени Институт химии силикатов им. И.В. Гребенщикова Российской академии наук (ИХС РАН) Способ эксплуатации в синхронном режиме частотно-регулируемых асинхронных двигателей с фазным ротором

Families Citing this family (4)

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Publication number Priority date Publication date Assignee Title
US10547269B2 (en) * 2018-05-17 2020-01-28 The Boeing Company Variable frequency independent speed motor
KR20210121254A (ko) 2019-02-09 2021-10-07 명남수 다중 다상권선 자가장 결속을 이용하는 전자기기계
WO2021037340A1 (fr) 2019-08-27 2021-03-04 Nrg Tech Ltd. Générateur électrique à induction à double alimentation
CN112383252B (zh) * 2020-10-30 2022-05-06 华北电力科学研究院有限责任公司 双馈发电机组励磁控制系统标幺方法及装置

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US4982147A (en) * 1989-01-30 1991-01-01 State Of Oregon Acting By And Through The State Board Of Higher Education On Behalf Of Oregon State University Power factor motor control system
US20150145466A1 (en) * 2012-04-30 2015-05-28 Snu R&Db Foundation Double wound rotor type motor with constant alternating current or direct current power supply input and control method thereof
US20150349687A1 (en) * 2014-05-30 2015-12-03 Abb Technology Ag Electric Power Generation and Distribution for Islanded or Weakly-Connected Systems

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US6894413B2 (en) * 2001-12-20 2005-05-17 Mitsubishi Denki Kabushiki Kaisha Permanent magnet dynamo electric machine, and permanent magnet synchronous generator for wind power generation
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JP5781785B2 (ja) * 2011-02-15 2015-09-24 トヨタ自動車株式会社 回転電機駆動システム
JP5838038B2 (ja) * 2011-04-22 2015-12-24 サンデンホールディングス株式会社 モータ制御装置
US9602192B2 (en) * 2013-01-30 2017-03-21 Hitachi, Ltd. Communication apparatus using radio waves between rotator and stator
EP2879280A1 (fr) * 2013-11-28 2015-06-03 NRG Tech Ltd. Machine électrique

Patent Citations (3)

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Publication number Priority date Publication date Assignee Title
US4982147A (en) * 1989-01-30 1991-01-01 State Of Oregon Acting By And Through The State Board Of Higher Education On Behalf Of Oregon State University Power factor motor control system
US20150145466A1 (en) * 2012-04-30 2015-05-28 Snu R&Db Foundation Double wound rotor type motor with constant alternating current or direct current power supply input and control method thereof
US20150349687A1 (en) * 2014-05-30 2015-12-03 Abb Technology Ag Electric Power Generation and Distribution for Islanded or Weakly-Connected Systems

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2694892C1 (ru) * 2018-10-15 2019-07-18 Федеральное государственное бюджетное учреждение науки Ордена Трудового Красного Знамени Институт химии силикатов им. И.В. Гребенщикова Российской академии наук (ИХС РАН) Способ эксплуатации в синхронном режиме частотно-регулируемых асинхронных двигателей с фазным ротором

Also Published As

Publication number Publication date
KR101992251B1 (ko) 2019-06-24
BR112018015726A2 (pt) 2022-03-03
AU2017223891A1 (en) 2018-07-19
US10790773B2 (en) 2020-09-29
KR20180102677A (ko) 2018-09-17
AU2017223891B2 (en) 2021-02-04
CN108702120A (zh) 2018-10-23
ZA201804518B (en) 2020-01-29
JP6571876B2 (ja) 2019-09-04
ES2770370T3 (es) 2020-07-01
EP3420633A1 (fr) 2019-01-02
EP3420633B1 (fr) 2019-12-18
WO2017144238A1 (fr) 2017-08-31
JP2019506122A (ja) 2019-02-28
US20190052212A1 (en) 2019-02-14

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